


City of Lost Children 2x20 [Speculation Fanfiction]

by thoughtsfromaclutteredbrain



Series: Supergirl Speculation Fanfiction [1]
Category: Supergirl (TV 2015)
Genre: Gen, city of lost children, none of these dynamics are romantic, speculation fanfiction, supergirl 2x20, they're just who is together in this fic
Language: English
Status: Completed
Published: 2017-05-04
Updated: 2017-05-04
Packaged: 2019-02-11 18:39:43
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,152
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12941331
Author URL: https://archiveofourown.org/users/thoughtsfromaclutteredbrain/pseuds/thoughtsfromaclutteredbrain
Summary: When the team gets a read on a large amount of energy, they go to investigate, and find themselves face to face with Rhea… And Lena Luthor. They square off against Rhea, but Mon El finds himself with an impossible choice to make. This encounter has Lena Luthor putting pieces together, while Mon El falls apart.





	City of Lost Children 2x20 [Speculation Fanfiction]

**Author's Note:**

> ***This fic was written on Tumblr before 2x20 aired
> 
> Ok guys, after seeing THESE PROMO PICS, my mind went a little crazy on how something like this could happen. This fic is basically my speculation on what may happen in 2x20. The ideas came together after talks with @busysciencegeek, @somos-poeiraestelar and @myfangirlinghq on Tumblr.

  
  


“Whoa guys…” Winn exclaimed, turning from his computer to face the team. After the incident at CatCo, Kara and Mon El had went back to the DEO to regroup. James had stayed behind to comfort Eve; the poor girl was traumatized. After that, he had went to search for the little boy that was there as well.

“What is it, Winn?” J’onn asked, sounding as level headed as always.

“Does this have anything to do with Rhea?” Kara cut in, moving from the round table in the middle of the DEO to Winn. Mon El and J’onn followed her, all crowding around his computer.

Winn spun back around and started gesturing towards the screen. “I’ve been tracking any abnormal energy hits… And boy, did we just get a hit.” He pointed at a pulsing marker on the screen. “Right here… Is emanating an insane amount of energy.”

“Are we sure it’s her?” Mon El asked, folding his arms in front of him. Kara gave him a sad smile and placed a hand on his shoulder. He sounded uneasy, and she knew that despite how hard it was, Mon El always wanted to believe the best of his mother. 

Winn clicked into the marker and whistled. “Yup. The read on this energy is from an element that doesn’t exist…” He started typing on his keyboard, opening windows left and right. “It would probably be about a 260 on the table of elements.”

Mon El let out an audible sigh, and J’onn patted him on the back. “What exactly is there?”

Winn smiled and continued to furiously type on his keyboard. “Ooh… Good question, J’onn. This building… is housing a generator ring.” His eyebrows shot up, and as he spoke, he got more frantic. “With the existing generator ring and this energy, she could be making a transmatter portal like the one we used for Slaver’s Moon. This is some Stargate-level stuff, guys.” 

He turned around to look at the group. All eyes fell on Mon El, who was clenching his jaw. “I’m sorry, buddy.” Winn knew exactly what Mon El was feeling, having a villainous parent of his own.

She’s never going to stop, Mon El thought. He knew that his mom was relentless, but he had really hoped that his mom would change and see that he was happy here. His father was able to see that, a fact that he would be forever grateful for. 

“I’ll assemble a team to check it out,” J’onn stated and started to walk away, but Winn stopped him. “You don’t have time for that. Whatever she’s planning she’s doing it now.”

Kara grabbed J’onn’s arm. “We’ll go check it out.” She looked back at her boyfriend, silently asking him if he was up to this mission. He responded by simply nodding.

J’onn looked between both of them. “Fine. But I’m coming too.” 

★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ 

They arrived outside the building a couple of minutes later.

Kara walked up to their entrance, and looked to J’onn and Mon El over her shoulder. “You ready, guys?”

J’onn nodded, switching to his human form. Mon El gave her a curt nod. She was concerned about him, but she knew he could handle himself against his mother. This wasn’t the first time they had faced each other. She just hoped this time would end better than the last.

They entered the building and looked around. It was some sort of lab that was super high tech. Kara half expected Rhea to be there by herself, so she was surprised to see other people there.

“Are you seeing this?” Kara asked Winn over her comms, hoping that he was getting a good picture over her body cam.

“Yup.” He responded. “Evil lab… Got it. You need to look for a huge ring shaped thingy.” 

“Split up.” J’onn suggested. They all nodded and broke apart to search.

Kara didn’t have to go far, however, before she was face to face with the generator. Not only that, but Rhea was right in front of it, showing something on a tablet to the woman she was with.

“Rhea.” Kara said, announcing herself to the women. They both turned around, and Kara was taken aback when she saw who Rhea was with. 

“Lena?” Kara asked, her shock evident.

Lena smiled, and then cocked her head a bit. “Supergirl? What are you doing here? I’m not in any danger… For once.” She let out a little chuckle.

Kara’s brain was firing a mile a minute, bit she tried to keep her voice even. “Lena, I don’t know what she has told you, but she can’t be trusted. You need to go.”

Lena met her with a surprised face, and before Lena could say anything, Winn was talking to her over her comms again.

“Kara, that building is owned by LCorp. Lena is working with her.”

Kara’s eyes widened. “Lena… You’re working with Rhea?”

Lena took a step forward, and put her hands out to her sides. “Yeah, I mean… This technology we’re developing… It’s gonna change the world… It’s has so many beneficial applications…”

“Yeah, but that’s not what she’s planning to use it for,” Kara interrupted, glaring at Rhea.

“You Kryptonians always think you know best,” Rhea spat, walking slowly towards Kara.

“Lena, get out of here,” Kara warned her, and focused her attention back on Rhea. She thought she saw Lena leave from the corner of her eye, but she couldn’t be sure.

“You stole my son from me… My world from me…” Rhea circled Kara as she spoke, every word hard, calloused and measured. “It’s only fair I do the same.”

Kara balled her hands into fists as J’onn and Mon El came to her sides.

Rhea just laughed at them. “A Martian, a Kryptonian and a coward.” She turned her head and spoke to the scientists behind her. “Get them.”

Ten of the scientists around them charged forward, pulling guns out of their coats. “Whoa, they are not scientists,” Winn commented over the comms.

“We’ve got this.” J’onn told Kara. “You go after her.”

Half of the men attacked J’onn and half attacked Mon El while Kara charged forward. She had to trust that she had trained Mon El well enough to be able to hold his own against these men.

Kara maneuvered around the men and was face to face with Rhea. Before she could say anything, Rhea smirked at her. “I was kind of hoping I’d get you to myself.”

Kara charged at her, grabbing her shoulders and pinning her against a support beam. She was careful to push her against it with enough force to trap her, but not to bring the whole place down.

“It’s over!” Kara yelled, her voice strained with the effort of fighting her.

“Oh no, Supergirl.” Rhea said, dragging out the name in her calm but mocking tone. “It’s only just begun.”

Rhea pushed her forward and turned them so Kara’s back was against the wall. J’onn came running to help her, his men discarded, but Rhea saw him coming and delivered a spinning back kick to his stomach, sending him flying.

Rhea punched at Kara, aiming for her head, but Kara moved out of the way just in time. She had spent enough time training Mon El to be comfortable with the speed the Daxamite was fighting her at, and she was a much better fighter than Rhea.

As Rhea’s fist connected with the wall, Kara swung a left hook, hitting her in the side of the face. Rhea crumpled to the ground, but before Kara could capitalize, Rhea was stabbing Kara in the back of the calf with one of her Kryptonite daggers. Man, did Kara hate those things.

Kara screamed and fell to the floor in a heap, and Rhea pinned her down by placing a heeled foot on her chest.

“Stop,” Mon El commanded. Kara hadn’t even realized that he had defeated the men attacking him, and she was mentally relieved. As she gazed up to look at his face, however, her eyes widened.

It was as if time itself had stopped, as Mon El stood pointing a gun at his own mother. He was surprised at himself for even having the willpower to do it, but when he saw her hurting Kara, his body jumped into action. He had taken the gun he wrestled out of one of the men’s hands, and before he could even stop himself, it was pointing at her. 

Rhea spun around, and when she saw the gun pointed at her, her eyes immediately filled with fear, but as she saw that it was her son holding it, her face softened.

“My son…” Rhea said patronizingly. “Has this woman really poisoned your mind that much that you would point a gun at your own mother?”

Mon El clenched his jaw, and balled his other hand up in a fist to control his anger. “I won’t let you keep hurting people.”

He was shocked by how even he was keeping his voice, how commanding he sounded. But after a lifetime of pretending to be something he wasn’t, it seems he had learned how to act pretty well.

“And I won’t,” Rhea stated, making him scoff at her. “If you would just come back home… Back to me.”

He felt tears welling in his eyes, and he willed them away. “You don’t want what’s best for me. You want what’s best for you! You are willing to destroy my world in this quest for… For what?”

“For you!” Rhea’s voice quivered, as if it was painful for her to speak. “Your world? You think this is your world? That these people are your family? I’m your family! I’m your tie to your old life.”

Rhea was going to say more, but Mon El interrupted her. “My old life?!?” His tears were free flowing at this point, but he was too focused on Rhea to stop them. He adjusted his grip on the gun and thrust it forward, making Rhea take a step back. He didn’t care that he was crying. He didn’t care that he was yelling. All he cared about was keeping everyone safe. Safe from her.

“You think I want my old life back?? The life of being a coward, a useless Prince? I hate myself for everything!! The things you did, the things I didn’t stop you from doing… I wish I could take it all back!!”

Mon El’s voice cracked on the last word, and he took a deep breath before he continued, his voice much lower. As hard as he tried, he couldn’t stop his voice from shaking. “But I can’t. All that I can do… The one thing I can do… Is stop you from hurting anyone else… Stop you for good.” 

Mon El’s mind was spinning. He felt his heart shattering, falling from his chest as he held the gun at his mother. He wanted to desperately to believe that there was some good left in her. That she could be changed like his father was. But he knew better. He knew she would not stop until she got what she wanted. So she had to be stopped. He had to stop her.

“Mon El… Don’t do this… You’re better than this…” He heard Kara’s pleading words, but they sounded far away. Everything felt far away. Nothing existed except for him and his mother.

“She’s not gonna stop!” he yelled to Kara, wherever she was. He thought he saw her inching to her feet from the corner of his eye, but he couldn’t be sure. All he could be sure of was that his mother had hurt her, and he wasn’t going to let her hurt Kara again.

“Mon El!” he heard J’onn chastising him, trying to break his attention. He wouldn’t be surprised if J’onn was trying to read his mind right now.

“Please,” Kara was begging him, and he felt his stomach churn when he realized that it didn’t matter. He didn’t have a choice. 

“This is the only way.” He was barely able to get the words out through his tears, and the words sounded as hollow as he felt.

“He’s really gonna do it.” He heard Winn’s incredulous voice over the comms, but it didn’t matter.

Rhea saw the determination in his eyes, and saw that he was actually considering shooting her. This wasn’t an empty threat anymore. She adjusted her dress and stood up straight. “All right then,” she said, her voice even and lacking any fear. “You want to shoot me? Kill your flesh and blood? Do it. At least I’ll be reunited with your father.”

Mon El felt his heart stop in his chest as he processed her words. The gun faltered in his hand for a minute, but he quickly held it with two hands instead.

“You’re lying,” he said through gritted teeth. He squeezed the handle of the gun so hard that he felt his fingers making indents into it.

“She’s not,” J’onn spoke up suddenly, sounding solemn. “I read her mind. Your father…”

“After you left the ship, he was so overcome with grief. He killed himself. You killed him… So it is only fitting that you kill me too.” 

Mon El felt his entire body go numb. He was sure Rhea was still talking, but he couldn’t hear her. He couldn’t hear anything except for her words echoing in his mind.

You killed him. You killed him. You killed him. 

“I’m sorry Mon El,” he heard J’onn’s voice echoing somewhere to his left.

Mon El tore his eyes away from Rhea to look at the Martian.

J’onn was shocked by Mon El’s face. He had never seen the Daxamite so sad, not even when he was told that his planet was a wasteland. He was sobbing, but there was something… cold… about his stance. Like he had nothing left to lose.

As soon as Mon El looked away from her, Rhea moved. She ran as fast as she could to her tablet. She pressed a button, turning on the transmatter portal. Once it was on she headed towards the portal itself.

The motion shocked Mon El back into reality, and he aimed his gun back at her, however she had already disappeared through the portal. He was too slow with his movement and shot the table with the tablet on it. It wasn’t a matter of hesitating, he just wasn’t fast enough. 

“I heard that. Is everyone alright?” Winn chimed in over the comms, concern evident in his voice from hearing the gunshot.

Kara ran to Mon El as he fell to his knees in a daze, hugging his shoulders tight. His body was shaking with sobs, and she held him close to her chest.

“We’re ok,” J’onn said, sounding a little unsure of himself as he stared at the couple. “We’re heading back to you now, Winn.”

J’onn turned his comm system off before Winn could say anything else. He went over and put a hand on Mon El’s shoulder, but he knew it would do nothing to ease his pain. He didn’t have to read his mind to know that Mon El was not alright. 

★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ 

Lena’s mind was spinning. Supergirl had told her to leave the building, but she knew that she would be the only one who could power down the portal if Supergirl needed her to. And it was her building, after all.

She didn’t know why Supergirl had come in the first place, and why she had attacked Rhea. Lena trusted Supergirl, that much was for sure. But… She had started to gain a connection to Rhea. Lena admired her, and she needed to know why Supergirl was after her.

So she stayed while Supergirl and Rhea fought. She kept herself by the door and out of harm’s way so that she wouldn’t be hurt, but could still watch. She saw Rhea stab Supergirl with something that made her fall hard to the ground.

So Rhea wasn’t the woman Lena thought she was. She wasn’t building this portal to help Earth. She was building it to destroy it. Lena had her doubts about Rhea when she found out she was an alien, but this was so much worse than anything she had ever imagined. And what’s worse, Rhea had convinced Lena to help her. She had manipulated her.

Lena was about to step in and help Supergirl when something happened that made her stop dead in her tracks.

“Stop.” One of the men that came with Supergirl had ordered, pointing a gun at Rhea. Rhea had turned around slowly and looked at him.

“My son…” she had said in a patronizing tone.

They had continued talking, but Lena wasn’t listening. The wheels were turning in her head. That face… The man looked familiar… And she swore she had heard the voice before…

She gasped as she put it all together. A couple of months ago, she had went to Catco and had invited Kara and her friend to her gala. While at the party, there had been an attack, and Kara’s friend had tried to help. He had failed miserably and was hit with the heat gun, but was unscathed, despite his burning suit.

But what she really remembered was how just a couple of days ago, she had went on a date with Jack. It had been awkwardly interrupted by Kara and her now-boyfriend Mike. This man looked exactly like him, just without the glasses. She was hit with a wave of understanding as she realized that Mike was Rhea’s son, the one who Rhea said betrayed her.

But that wasn’t it. That wasn’t all that Rhea had told her. Rhea had said that her son had met an “awful girl” who had stole him from her… That girl… It had to be Supergirl… Which meant…

No.

Lena felt her heart break as she put the final pieces together. She willed herself to find a flaw in her logic, but she couldn’t find any.

Whenever she had seen Mike… Or Mon El, as they were calling him, he had been with one person. Some could argue that he had become close to her. So close that if someone wanted to tear him away from her, he would have resisted.

Kara Danvers.

So if Mike… Mon El… was this man… Then…

Kara Danvers is Supergirl. 

Everything in her head clicked at that point. She had invited both Kara and Supergirl to that gala, but she had never seen them at the same time, despite that they were “good friends”. The time when Kara had came to her sniffing around about her mother. That one time that she had fallen off her balcony while on the phone with Kara and Supergirl had saved her. She even remembered in one of their first meetings, Kara had told her that she had “flew there on a bus.”

She couldn’t imagine how she had been so stupid. Now that she looked at Supergirl, she realized that if she imagined Supergirl with glasses, she would look exactly like Kara Danvers.

Kara had lied to her. Kara hadn’t told her she was Supergirl. Kara was the one person that Lena thought she could trust 100%, but she had been lying to her the entire time. 

Lena felt her entire body turning numb, and she was met with that cold calm that she had felt so often recently. Despite all the various things in her life, one constant was that the people she cared about most always betrayed her in the end.

She left the building before Supergirl… before Kara… noticed that she was still there. She needed time to think.

★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ 

Mon El busted into the DEO training room. He knew that he couldn’t hide out in there forever, but needed a few minutes to himself. The tears hadn’t been able to stop, and his entire body felt tired. But he was so angry.

Mon El screamed, a wild, primal scream that ripped through his throat and left it feeling dry. He didn’t even care who heard him. Months and months of suppressing his emotions, of suppressing his pain, was being let out. He slid down the wall and buried his head in his hands, not even bothering to try to dry the tears.

He almost shot her. He almost shot his own other. He was going to kill her, and not only that, he thought it was the right thing to do. 

All these months, he was trying so hard to change. To become a person who could inspire people and fill them with hope. He wanted to honor that, and be a person who rises up.

But as he stood there, face to face with his mother, all he could think about was stopping her and putting an end to the torment she was causing everyone. But if he was willing to kill her to keep everyone safe, was that the right thing to do? What did that say about him?

And if he was willing to kill his own mother, was he really better than her at all?

He felt an immense wave of pain and sadness wash over him, and he banged his head on the wall behind him so hard, he was sure he left a dent.

His mother was willing to kill everyone to get her son back. If he was willing to kill her to stay on this planet, then he really wasn’t better than her at all. He was still the same selfish person that had arrived on this planet all those months ago.

Mon El’s thoughts were interrupted when he door opened. He saw Kara peek in, and he looked away, feeling the tears start to flow even harder. He couldn’t even look at her. He had failed to be the person she thought he could become.

She tread carefully and slowly sat down next to him. She wrapped an arm around him, and though he felt he didn’t deserve it, he didn’t move away. 

“Hey.” Kara said softly, running his shoulder. “I’m sorry about your father… He was a good man.”

That was another situation entirely. He was so consumed with what he almost did that he hadn’t even had time to fully process his father’s death.

He had died because of Mon El. Everything bad that was happening… It was all his fault. Every last thing. He knew that every moment he stayed on this planet, he was putting it at risk. He was putting Kara at risk. But he couldn’t find it in himself to push her away and give up his new life. And he hated himself for it. 

Mon El didn’t even realize that he had said the last part out loud until he felt Kara squeeze his shoulder.

“Your father was not your fault.” He wanted to believe her, but he couldn’t. Not after what his mother told him.

He killed himself. You killed him.

“I almost… I was gonna…” He was racked with sobs, and he couldn’t find it in himself to finish the sentence.

“You were faced with an impossible choice.” Kara told him, her voice full of reassurance. “And you didn’t kill her.”

He didn’t add what he wanted to say. That he had wanted to kill her. Instead he just sighed. “You wouldn’t be in this situation if it wasn’t for me. You don’t have to make me feel better.” It wouldn’t help anyway, he thought to himself, but didn’t add.

Kara let out a tiny chuckle. Mon El couldn’t find any humor in the situation, and he had tried, so he was baffled to hear the sound. She gave him a small smile. “That’s what I told you when you almost died because of my parents…”

The joke wasn’t lost on him, but he couldn’t find it in himself to even fake a chuckle. He had been trying to hold back his grief for so long, and it had finally spilled over. Even now, he hated that he was crying on the floor in front of Kara, but he couldn’t stop the tears if he tried.

Kara rested her head on his shoulder. “We’ll get her. And we’ll stop her.”

Mon El felt his breath hitch in his throat at the thought of seeing his mother again.

“And what if I’m face to face with her again?” He whispered. He wasn’t even sure if he was asking Kara or himself. “What if…” His voice cracked, and Kara cut him off before he could continue.

“Then you’ll make the right choice.” She stated firmly. He couldn’t imagine how she could be so sure after what he almost did, but she did have a talent for believing the best in people.

He just nodded and sighed. He prayed to Rao that she would be right.

**Author's Note:**

> This is my first fic, so sorry if it’s not that good. This is my brain child of what I think may happen, and if I’m anywhere close to right, I’m EXCITED! And shoutout to bilgegungoren00 for being the BEST BETA EVER!
> 
> [I am also on Tumblr under the same name, thoughtsfromaclutteredbrain]


End file.
